Conventional agriculture destroys our soils, pollutes our water and is a major contributor to climate change. What if our agricultural practices could stabilize, or even reverse these trends? explores the dual function of biochar as a carbon-negative energy source and a potent soil-builder. Created by burning biomass in the absence of oxygen, this material has the unique ability to hold carbon back from the atmosphere while simultaneously enhancing soil fertility. Author Albert Bates traces the evolution of this extraordinary substance from the ancient black soils of the Amazon to its reappearance as a modern carbon sequestration strategy. Combining practical techniques for the production and use of biochar with an overview of the development and future of carbon farming, describes how a new agricultural revolution can reduce net greenhouse gas emissions to below zero while increasing world food reserves and creating energy from biomass wastes. Biochar and carbon farming can: Biochar is not without dangers if unregulated, and it is not a panacea, but if it fulfills its promise of taking us back from the brink of irreversible climate change, it may well be the most important discovery in human history.